Comment 2 for bug 1878720

Root Cause:

CephAnsibleEnvironmentVariables data is supposed to be transformed into "KEY=VALUE" format by yaql expression.

```
ceph_ansible_environment_variables:
  yaql:
    data: {get_param: CephAnsibleEnvironmentVariables}
    expression: $.data.items().select($[0] + '=' + $[1])
```

However, the expression here use `+` to join the key($[0]) and value($[1]), which will cause syntax error when value is not string type.